Piano-plate.



PATENTED JULY 11, 1905.

J. DAVENPORT. PIANO PLATE.

APPLICATION FILED NOV. 29, 1904.

WITNESSES.-

L. ZM.

Attorney;

UNITED STATES Patented July 11, 1905.

JOHN DAVENPORT, OF STAMFORD, CONNECTICUT.

4 PIANO-PLATE.

SPECIFICATION forming part of Letters Patent No. 794,664, dated July 11,1905,

Application filed November 28, 1904:. Serial No. 234,517.

To whom it may concern:

Be it known that 1, JOHN DAVENPORT, a citizen of the United States, anda resident of Stamford, in the county of Fairfield and State ofConnecticut, have invented certain new and useful Improvements in Piano-Plates, of which the following is a specification.

My invention relates to an improved construction of piano-plates such asis employed to support the strings in all styles of pianos.

Numerous designs of piano-plates have and are being made for thedifferent manufacturers of pianos, which plates are all cut away more orless and are also braced in different ways; but so far as I- am awareall of these different styles of plates are mostly formed of cast metaland usually in one piece. These cast-metal plates are reinforced aroundtheir edges and through the webs of the cutaway portion to properlystrengthen and brace the plate against the enormous strain applied withthe tightening of the wire strings which are attached to the pins in therespective bridges. The best metals are usually employed from which tocast these plates, yet they not infrequently break after the strings areattached and as a result of the strain resulting therefrom. This,together with the excessive weight and great amount of labor required inproducing and finishing these cast plates, renders them objectionable,and it is with a view of overcoming said objections and improving thetone of the piano that I have devised my improvement.

It is therefore the object of this invention to produce a piano-platefrom a series of sections of rolled, drawn, or pressed sheet metalproperly formed and secured together in a way to produce a lighter platethan would be practical from cast-iron, and to give greater strengththrough the braces and other portions where the cast plates are usuallyweak, and, further, to make it possible to produce a plate Whosesound-conducting properties will be greatly enhanced, and, finally, toproduce a late which may be manufactured and finis ed in quantitiescheaper than is possible from cast metal.

With the above and other objects in view I have devised the novelconstruction and combination of parts shown upon the accompanying twosheets of drawings, forming a part of this specification, upon whichsimilar characters of reference denote like or corresponding partsthroughout the several figures, and of which Figure 1 shows a frontelevation of a popular design for piano-plate constructed in ac cordancewith my idea. Fig. 2 is a crosssectional view taken on line 2 2 ofFig. 1. Fig. 3 is a detail side elevation of a brace employed in myconstruction, the same being shown as viewed from the arrow 3 in Fig. 1and bent to accommodate the under or treble strings in the middlesection. Figs. 4 and 5 are detail cross-sectional views taken on lines 44 and 5 5, respectively, of Fig. 1.

The main body of the plate may be formed of sheet-steel of aboutone-half the thickness required in cast metal and may be stamped out orsawed, as preferred, and likewise of any particular design required tomeet the fancy or requirements of the numerous makers. In the stampingof these bodies the numerous holes (not shown in the drawings, butrequired in all piano-plates for the location of screws, tuning-pins,&c.) may also be punched, thereby saving a great amount of labor overthe present drilling process.

Referring in detail to the characters of reference marked upon thedrawings, A indicates the body or frame, which, as shown, is formed froma single piece of sheet metal, being cut away in the usual way to permitthe sounds to pass therethrough, but having suitable Webs of varyingwidth to reinforce the body and to accommodate the reinforcing-strips,all of which would be preferably formed of rolled, stamped, or pressedsheetsteel. thereto upper reinforcing-strips d and e, forming a border,which may be formed of halfround or other shaped steel strips, while thebottom edge is preferably provided with aflat strip j, secured in thesame way.

g, h, i, and indicate tying and reinforcing braces of rolled or pressedstructural steel of any preferred shape and best adapted to tie Thebody, as illustrated, has riveted the upper and lower portions of theplate together and to stiffen, brace, and strengthen the platethroughout. The particular design and number of these braces, as alsothe other attached strips, may be varied to obtain the best results andto produce plates of different designs. The brace 9 (shown in detail inFigs. 2 and 3) is shaped to form a loop 7r to accommodate the under lineof strings (not shown) extending from the lower end of the hitch-pinsection Z up over the upper bridge-bearing m and back-bearing n,attached to tuning-pins in the upper portion of the plate, but not shownin the drawings. The hitch-pin section is shown reinforced withsheet-metal strips of the desired shape attached thereto with a doubleline of rivets. The bridge and back bearing strips m and n, riveted tothe upper portion of the body, would preferably be formed of rolledsteel and each contain a central raised portion and obviously serve as abearing over which strings are drawn and tightened by the tuning-pins.(Not shown, but located above.)

0 indicates the upper bass-bridge, which, like the lower bass-bridge p,is formed of structural steel of any preferred shape. These two bridgesin practice each support a row of pins (not shown) to the lower row ofwhich the bass-strings (not shown) are connected and are drawn over theupper ones to the tuning-pins. a

(1 indicates a further attached strip of rolled steel by means of whichthe outer edge is reinforced.

r indicates an attached steel strip to form a back-rib bearing, as shownin dotted lines in Fig. 1.

it will be obviously apparent that the various steel strips attached tothe body of the plates are preferably secured by means of rivets, asindicated, and that any number of such rivets or their particularlocations may be varied as the manufacturer may deem advisable.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is

1. A piano-plate formed of rolled metal and comprising a sheet-metalbody having its edges, bridges and brace-sections reinforced.

2. A piano-plate formed of rolled metal and comprising a sheet-metalbody and steel strips attached to its edge, bridge and brace portions toreinforce the same.

As a new article of manufacture, a plate for an upright piano formed ofrolled steel and comprising a body forming an upper and lower portion,steel strips attached to the edge, bridge and brace portions of theplate.

4. As a new article of manufacture an upright-piano plate formed ofrolled steel and comprising a body forming an upper and lower parthaving narrow connecting-braces, and separate brace-strips attached tosuch narrow portions and extending from one part to the other.

5. A piano-plate comprising a rolled sheetmetal body portion and rolledsteel strips attached to its bridge portions to raise and strengthen thesame.

6. A piano-plate formed of rolled metal and comprising a body out fromsheet metal, steel strips attached to said body to reinfmce the edges,brace sections secured to the body to stiffen the same, and rolled steelpieces secured to said body to form the several bridges for the strings.

7. As a new article of malnrfacture a pianoplate formed of rolledsheet-steel and comprising a body having oppositely-loealml bridgeportions and steel strips attached to such bridge portions, attachedsteel strips extending transversely to and intermediate of such bridgeportions to form braces.

S. A piano-plate comprising a rolled sheetmetal body and steel. stripsattached to its bridge and brace portions to reinforce andv strengthenthe same.

Signed at Stamford, in the county of Fairfield and State of Connecticut,this 22d day of November, A. l). 1904.

JOH N 1) AV IQ N P (1) RT.

l/Vi tn esses

